Nowadays thermoacoustic engines are commonly used as heat pumps or refrigerators. The thermoacoustic engines utilize energy associated with thermoacoustic waves to generate electrical energy.
In existing technologies, usually thermoacoustic engines receive heat from a heat source and use a large part of the heat to generate thermoacoustic waves. Further, energy associated with the thermoacoustic waves may be used to perform various types of works. In order to use the energy associated with the thermoacoustic waves, the thermoacoustic engines use a hot heat exchanger and a cold heat exchanger. A porous structure may be configured between the hot heat exchanger and the cold heat exchanger. The porous structure is made up of one or more of metal foils, a metal mesh, a sheet of a foamed metal, and sheets of filter paper. Additionally, the thermoacoustic engines may include one or more moving parts and moving masses to generate the thermoacoustic waves. Further, the one or more moving parts and moving masses require sliding seal mechanisms for their operation. The thermoacoustic waves are generated based on pressure and volume oscillations of a fluid within the thermoacoustic engines. The pressure and volume oscillations of the fluid are generated using the heat energy received from the heat source and movements of the one or more moving parts and moving masses. During operation, high pressure is created within the thermoacoustic waves for generating thermoacoustic waves.
Further, a free piston mechanism may be used to reduce complexities in using the one or more moving parts and moving masses in the thermoacoustic engines. The free piston mechanism in the thermoacoustic engines utilizes gas springs to generate the thermoacoustic waves. The gas springs in the thermoacoustic engines work similar to mechanical pistons, thereby, partially eliminating the need of sliding seal mechanisms. However, the use of the moving masses in the thermoacoustic engines is still required in such thermoacoustic engines.
Therefore, there is a need for a travelling wave thermoacoustic piezoelectric apparatus and a travelling wave thermoacoustic piezoelectric system for generating electrical energy from heat energy using thermoacoustic waves.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention.